Piston ring



Dec. 23, 1941. T. A. BOWERS 2,267,369

A Pls'ror;V RING lFiled Aug. 4,1939 2 sheets-sheet 1 Dec. 23,l 1941. T. A. BOWERS 2,267,369

. PIsTN RING l Filed Aug. 4, 1939 I 2 Sheets-Sheet 2 'imi' A Patented Dec. 1 941 s PATENT OFFICE PISTON RING? Thomas A. Bowers, Boston, Mass., assigner to Power Research Corporation, Boston, corporation of Massachusetts Mass., a

Application August 4,1939, Serial No. 288,386

1'0 Clarins. (ci. 309-445) This invention relates to` piston rings and more especially to a piston ring formed from a strip of piston ring material;

. In my co-pending application, Ser. No. 268,721

` flied April 19, 1939, reference has been made to diflicultiesin maintaining proper distribution of oil in cylinders, particularly worn cylinders, at high engine speeds, and I have described and claimed ring structures formed from vresilient piston ring material. Y

A chief object of this invention isl to provide improved ring structures, of the same general ,character, for leffecting oil distribution on a cylinder wall with a view to particularly overcoming faulty oil distribution in cylinders which have become worn and which are subject to highspeed operation. lIhe invention also aims to devise a simple, cheap and eillcient piston ring structure and method of manufacture, in which a single strip of piston ring material is formed and fabricated into a piston ring in an improved manner.

The nature of the invention will be readily un'- derstood from the following description when read in connection with the accompanying drawings, and the novel features will be more particularly pointed out in the appended claims.'

In the drawings:

Fig. 1 is a perspective view of a strip of piston ring material as employed in my invention.

Fig. 2 is a plan view illustrating a step of forming aV strip of material such as thatshown inI Fig. 1 with o il scraping portions.

Fig. 3 is a perspective view illustrating a further step of reversely folding upon itself the formed material of Fig. ii.r

Fig. 4 is an elevational view illustrating astill further step in the formation of a ring body from a material such as shown in Fig; 3.

' Fig. 5"is a perspective view fragmentarily illustrating a finished ring resulting from indicated in Fig. 4. v

Fig. 6 is an 'assembly'viewfragmentarily illus- .shown in Fig. 8a.

lshed ring formed from a Vmaterial such as that Fig. 10 is a perspective view fragmentarily illustrating a further modification of ring formed from a strip such as that shown in Fig. 8a.

Fig. 1l illustrates the ring indicated in Fig. 9 mounted in a piston and cylinder.

Fig. 12 illustrates association of the ring'indicated in Fig. 10 with a piston and cylinder,

Fig. 13 is a perspective view illustratingv another strip of piston ring material.

Fig. 14 is avplan view illustrating a modified stamping step effected on a strip of material such as that illustrated in' Fig. 13.

Fig. 15 is a detail view in partial cross section illustrating a single folding of the material in dicated in Fig. 14.

Fig. 16 is an elevational view fragmentarily il- ,lustrating a finished ring formed from material suchas that indicated in Fig. 14; and

Fig. 17 is a view in cross section illustrating a l piston and -cylinder assembly.

trating a piston and cylinder with a ring such as that shown in Fig. 5 associated therewith.

Fig.,7 is a modification of the ring illustrated in Fig. 5.

Fig. 8 is another assembly view illustrating the association of a ring such as that indicated in Fig. 'l with a piston and cylinder.

Fig. 8a is a fragmentary plan view illustrating In accordance with my invention, I provide a strip of piston ring material l, which may preferably be composed of steel, although other suitable materials may be employed if desired. I treat this ribbon by cuttingand folding operations to produce improved types of oil scraping edges in a ring structure. A

Fig, 2 illustrates a cutting operation as for example punching, by which it kwill be observed that there are found in the strip I oil-scraping portions 2 occurring at one sideV of a body portion 3, and relatively larger oil scraping-portions il occurring at an opposite side'of the 'body portionj3. i In carrying out the punching operation, I may also' provide circular openings 5 connecting with lines of cutting 6 for facilitating bending of the body portion 3 reversely upon itself.

In Fig. 3 the body portion 3 has been reversely folded to comprisean open structure in which oil scraping edges "2 and 4 are alternately disposed in spaced-apart rows at opposite sides of the body portion.v It; will be observed that the body portion 3 has been neatly folded at the openings A'structure with gaps 2* occurring between pora .stamping or cutting out operation similar to that indicated in Fig. 2.

Fig. 9 is a perspective view illustrating a tions 2.

In Fig. i I have illustrated the further step of folding the oil scraping portions 4 over upon the oil scraping portions 2 along the line of bending I, to comprise double oil scraping edges. The structure is thereafter compacted into an annular body in which the scraping edges described -a strip of piston ring material.

comprise an outer contacting periphery. It will be noted that the edges l and 8 are offset with respect to edges 8 and Il, and the oil scraping portions I occur in an overlying manner with respect to the gaps between any two adjacent oil scraping portions 2 so that there results a sealing action to prevent oil from passing through the gaps 2* in the ring structure at its top and bottom.

In Fig. 5 the arrangement of the oil scraping portion l has been more clearly illustrated and it will be seen that Vthe innerperlphery of the ring comprised by rounded edges II. It vshould also tween points of bending of the body Iportion 3, which, in v'addition to the staggered relationship of the gaps already described, tends to further preclude the passage of oil through the top or bottom of the ring. 'I'he 'covering of spaces I2 is also illustrated in Fig. 6 in which the ring of Fig. 5 has been shown associated about a piston I` with the double edges engaged against 'a cylinder wall IOP.

In Figs. '7 and 8.1 have illustrated a modified arrangement of ring formedfrom a material such as Ythat indicated in Fig. 4. In this modification, the reversely folded material is compacted into an annular body in an opposite manner so that the rounded edges n occurring -from folding over the portions! upon the portions 2 comprise the outer periphery of the ring and present oil scraping edgesv adapted to contact the 'cylinder wall'IS when assembled in a piston I4, and seen in Fig. 6. This arrangement of oil scraping edges has the advantageA of providing a lrounded form which may allow-a quicker wearing ini of the 4ring against a cylinder wall.

In Figs. 8 and 9, I have illustrated another modified method of forming a piston ring from I provide a stamping I5 from a strip of piston ring material, which is provided with cut out oil scraping portions I6 along only one side of the strip of material. The strip of material is reversely folded upon itself in the manner already described, and

the oil scraping -portions IB are then folded over of this modification of ring structure is to provide a simple rounded oil scraping Vedge which may be quickly worn in on a cylinder wall' I8 as shown in Figs. 11 and 12.

In Figs. 13-17 inclusive, I have shown still an- 1 other modified method of forming'a piston ring structure from a single ribbon of material. A strip I9 is punched out or cut in some other desirable manner to.present a structure such as that shown in Fig. 14 in which there occurs a body portion having oil scraping portions 2|. In this modification, the body portion 2|! is'reversely folded upon angular lines of bending 22 edgeot the body portion 2l. It will be noted that the body portion 2l at one side will be bent in an arcuate manner as shown in Fig. 16, while at its rear and lower edge it will be substantially vertical as shown in Fig. 16. It will be seen that in theconstruction shown I have devised a piston ring structure from a single length of piston ring material which effects novel sealing at its top and bottom and which develops 'a desirable wall pressure adapted to eiiiciently distributing oil on a cylinder.- Also novel modiiications for improving the forming of rings and their operationhave been set forth.

It is intended that various changes in the structure and steps employed may be resorted to in keeping with the spirit of the invention.

I claim:

1. A piston ring comprising spaced-apart sides, connecting portions for the sides, saidl sides formed from a plurality of segments arranged in contiguous relation and extending beyond the connecting portions in a direction radially outward of the ring, each o f said segments having bent portions which provide` rounded edges constituting portions of a peripheral edge of the ring.

2. A piston ring comprising spaced-apart sides, connecting portions for the sides, said sides formed from a plurality of segments arranged in annular spaced-apart rows, each of4 said segments having bent portions which extend along a peripheral edge lo f the ring in a direction circumferentially thereof.

3. A piston ring comprising a plurality of T- necting web portions for the rows. each of said 1 segments having a bent peripheral edge which extends axially of the ring.

4. A piston ring comprising spaced-apart sides, connecting webs for the sides, said sides including a plurality of segments of piston ring material arranged in contiguous relation in annular rows, said sides further including rows of relatively greater segments attached along edges. of the said first segments and adapted to overlap points of abutment of the said iirst segments.

v 5. A piston ring comprising spaced-apart sides. connecting portions for the sides, each of said sides including a row of contiguously arranged segments, other segments overlying the said rst segments and being connected to the said rst segments by bent portions which extend circumferentially along one of the peripheral edges of v`the ring.

`ring material connected together at the n inner l periphery of the ring.

'1. A piston ring comprising a plurality of segments of piston ring material'arranged in contiguous relation to formspaced-apart annular. rows, said rows connected by web portions, each of said segments having a relatively larger overlying crown portlon which extends circumferen- -tially of the ring in overlapping relation with respect to a point of abutment of two of the said Y nrst segments.

which results in one side of thering being formed lower than the other, and as before the oil scraping portions 2i are bent along the lines of bending 23 and shaped to coincide with the opposite 10, A piston ring comprising upper and lower land surfaces, said land surfaces formed with a plurality of contiguously arranged segments, connecting portions for the segments in the respective land surfaces, said connecting portions being bent into an arcuate shape at one side thereof to form a ring of a `greater axial height at its outer periphery than at .its inner periphery.

THOMAS A. BOWERS. 

